1. Field of the Invention
The present invention relates to an apparatus for controlling a rotation of a turret disc in a turret type yarn winder based on the detected contact pressure between a yarn package and a roller bail.
2. Description of the Related Arts
A yarn winder has been already disclosed in Japanese Unexamined Patent Publication (Kokai) No. 2-255468, in which a displacement of a roller bail supported by an arm to be in contact with a yarn package is detected by a proximity switch and a turret disc is positively made to rotate in a normal direction based on the detected signal so that an increase of a package diameter is absorbed thereby, while adjusting a contact pressure onto the yarn package, i.e., a pressing force of the roller bail against the yarn package by the adjustment of a spring stiffness.
According to the above turret type yarn winder of the prior art, since the positional control of the roller bail based on the rotation of the turret disc and the adjustment of a contact pressure are carried out independently from each other, it is necessary to vary a spring stiffness and determine conditions by detecting loads (contact pressures) applied thereby on the roller bail at the respective positions at which the control is carried out, whereby a prompt and accurate adjustment is difficult. Particularly, when a plurality of turret type winders are densely arranged in multiple stairs and rows, the contact pressure adjustment is very complicated because it is necessary to determine the contact pressure of the respective winder by the individual mechanical adjustment.